Add --waveout-buffers switch for Windows users.

media/audio/audio_util.cc

Index: media/audio/audio_util.cc
diff --git a/media/audio/audio_util.cc b/media/audio/audio_util.cc
index e67dd8e8246286c642908b144ed1c97deea09efc..8df373940716a76f57c506e9c06d81c25e8ac453 100644
--- a/media/audio/audio_util.cc
+++ b/media/audio/audio_util.cc
@@ -339,6 +339,14 @@ size_t GetHighLatencyOutputBufferSize(int sample_rate) {
 #if defined(OS_WIN)
 
 int NumberOfWaveOutBuffers() {
+  // Use the user provided buffer count if provided.
+  int buffers = 0;
+  std::string buffers_str(CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
+      switches::kWaveOutBuffers));
+  if (base::StringToInt(buffers_str, &buffers) && buffers > 0) {
+    return buffers;
+  }
+
   // Use 4 buffers for Vista, 3 for everyone else:
   //  - The entire Windows audio stack was rewritten for Windows Vista and wave
   //    out performance was degraded compared to XP.